[mirror_ubuntu-artful-kernel.git] / lib / ucs2_string.c

#include <linux/ucs2_string.h>
#include <linux/module.h>

/* Return the number of unicode characters in data */
unsigned long
ucs2_strnlen(const ucs2_char_t *s, size_t maxlength)
{
        unsigned long length = 0;

        while (*s++ != 0 && length < maxlength)
                length++;
        return length;
}
EXPORT_SYMBOL(ucs2_strnlen);

unsigned long
ucs2_strlen(const ucs2_char_t *s)
{
        return ucs2_strnlen(s, ~0UL);
}
EXPORT_SYMBOL(ucs2_strlen);

/*
 * Return the number of bytes is the length of this string
 * Note: this is NOT the same as the number of unicode characters
 */
unsigned long
ucs2_strsize(const ucs2_char_t *data, unsigned long maxlength)
{
        return ucs2_strnlen(data, maxlength/sizeof(ucs2_char_t)) * sizeof(ucs2_char_t);
}
EXPORT_SYMBOL(ucs2_strsize);

int
ucs2_strncmp(const ucs2_char_t *a, const ucs2_char_t *b, size_t len)
{
        while (1) {
                if (len == 0)
                        return 0;
                if (*a < *b)
                        return -1;
                if (*a > *b)
                        return 1;
                if (*a == 0) /* implies *b == 0 */
                        return 0;
                a++;
                b++;
                len--;
        }
}
EXPORT_SYMBOL(ucs2_strncmp);

unsigned long
ucs2_utf8size(const ucs2_char_t *src)
{
	unsigned long i;
	unsigned long j = 0;

	for (i = 0; src[i]; i++) {
		u16 c = src[i];

		if (c >= 0x800)
			j += 3;
		else if (c >= 0x80)
			j += 2;
		else
			j += 1;
	}

	return j;
}
EXPORT_SYMBOL(ucs2_utf8size);

/*
 * copy at most maxlength bytes of whole utf8 characters to dest from the
 * ucs2 string src.
 *
 * The return value is the number of characters copied, not including the
 * final NUL character.
 */
unsigned long
ucs2_as_utf8(u8 *dest, const ucs2_char_t *src, unsigned long maxlength)
{
	unsigned int i;
	unsigned long j = 0;
	unsigned long limit = ucs2_strnlen(src, maxlength);

	for (i = 0; maxlength && i < limit; i++) {
		u16 c = src[i];

		if (c >= 0x800) {
			if (maxlength < 3)
				break;
			maxlength -= 3;
			dest[j++] = 0xe0 | (c & 0xf000) >> 12;
			dest[j++] = 0x80 | (c & 0x0fc0) >> 6;
			dest[j++] = 0x80 | (c & 0x003f);
		} else if (c >= 0x80) {
			if (maxlength < 2)
				break;
			maxlength -= 2;
			dest[j++] = 0xc0 | (c & 0x7c0) >> 6;
			dest[j++] = 0x80 | (c & 0x03f);
		} else {
			maxlength -= 1;
			dest[j++] = c & 0x7f;
		}
	}
	if (maxlength)
		dest[j] = '\0';
	return j;
}
EXPORT_SYMBOL(ucs2_as_utf8);
Commit	Line	Data
0635eb8a MG	1	#include <linux/ucs2_string.h>
	2	#include <linux/module.h>
	3
	4	/* Return the number of unicode characters in data */
	5	unsigned long
	6	ucs2_strnlen(const ucs2_char_t *s, size_t maxlength)
	7	{
	8	unsigned long length = 0;
	9
	10	while (*s++ != 0 && length < maxlength)
	11	length++;
	12	return length;
	13	}
	14	EXPORT_SYMBOL(ucs2_strnlen);
	15
	16	unsigned long
	17	ucs2_strlen(const ucs2_char_t *s)
	18	{
	19	return ucs2_strnlen(s, ~0UL);
	20	}
	21	EXPORT_SYMBOL(ucs2_strlen);
	22
	23	/*
	24	* Return the number of bytes is the length of this string
	25	* Note: this is NOT the same as the number of unicode characters
	26	*/
	27	unsigned long
	28	ucs2_strsize(const ucs2_char_t *data, unsigned long maxlength)
	29	{
	30	return ucs2_strnlen(data, maxlength/sizeof(ucs2_char_t)) * sizeof(ucs2_char_t);
	31	}
	32	EXPORT_SYMBOL(ucs2_strsize);
	33
	34	int
	35	ucs2_strncmp(const ucs2_char_t a, const ucs2_char_t b, size_t len)
	36	{
	37	while (1) {
	38	if (len == 0)
	39	return 0;
	40	if (a < b)
	41	return -1;
	42	if (a > b)
	43	return 1;
	44	if (a == 0) / implies b == 0 /
	45	return 0;
	46	a++;
	47	b++;
	48	len--;
	49	}
	50	}
	51	EXPORT_SYMBOL(ucs2_strncmp);
73500267 PJ	52
	53	unsigned long
	54	ucs2_utf8size(const ucs2_char_t *src)
	55	{
	56	unsigned long i;
	57	unsigned long j = 0;
	58
cf289cef	59	for (i = 0; src[i]; i++) {
73500267 PJ	60	u16 c = src[i];
73500267 PJ	61
a6807590	62	if (c >= 0x800)
73500267	63	j += 3;
a6807590	64	else if (c >= 0x80)
73500267 PJ	65	j += 2;
	66	else
	67	j += 1;
	68	}
	69
	70	return j;
	71	}
	72	EXPORT_SYMBOL(ucs2_utf8size);
	73
	74	/*
	75	* copy at most maxlength bytes of whole utf8 characters to dest from the
	76	* ucs2 string src.
	77	*
	78	* The return value is the number of characters copied, not including the
	79	* final NUL character.
	80	*/
	81	unsigned long
	82	ucs2_as_utf8(u8 dest, const ucs2_char_t src, unsigned long maxlength)
	83	{
	84	unsigned int i;
	85	unsigned long j = 0;
	86	unsigned long limit = ucs2_strnlen(src, maxlength);
	87
	88	for (i = 0; maxlength && i < limit; i++) {
	89	u16 c = src[i];
	90
a6807590	91	if (c >= 0x800) {
73500267 PJ	92	if (maxlength < 3)
	93	break;
	94	maxlength -= 3;
	95	dest[j++] = 0xe0 \| (c & 0xf000) >> 12;
a6807590	96	dest[j++] = 0x80 \| (c & 0x0fc0) >> 6;
73500267	97	dest[j++] = 0x80 \| (c & 0x003f);
a6807590	98	} else if (c >= 0x80) {
73500267 PJ	99	if (maxlength < 2)
	100	break;
	101	maxlength -= 2;
a6807590 JA	102	dest[j++] = 0xc0 \| (c & 0x7c0) >> 6;
a6807590 JA	103	dest[j++] = 0x80 \| (c & 0x03f);
73500267 PJ	104	} else {
	105	maxlength -= 1;
	106	dest[j++] = c & 0x7f;
	107	}
	108	}
	109	if (maxlength)
	110	dest[j] = '\0';
	111	return j;
	112	}
	113	EXPORT_SYMBOL(ucs2_as_utf8);